The present invention relates to a conduit pipe for a telecommunication cable; and, more particularly, to a conduit pipe which is divided longitudinally into a plurality of divided bodies for easy carriage and installation.
Conventionally a telecommunication cable is installed by taking following steps: forming manholes with a predetermined distance, burying an exterior pipe which is to function as a cable tunnel, installing a plurality of conduit pipes in the exterior pipe and arranging telecommunication cables within the conduit pipes.
FIG. 1 is a schematic drawing of a cable tunnel built by using a conventional method and FIG. 2 is a cross-sectional view of the cable tunnel with conventional conduit pipes installed therein. As shown in FIG. 1, manholes 1 and 1xe2x80x2 are disposed tens or hundreds of meters apart from each other, and a typical distance between two adjacent manholes is 246 m. An exterior pipe 2 for building the cable tunnel is buried between the manholes 1 and 1xe2x80x2. A plurality of conduit pipes 3 are installed within the exterior pipe 2. As illustrated in FIG. 2, a telecommunication cable 4 is laid within the conduit pipe. The exterior pipe generally has a diameter big enough to accommodate some additional conduit pipes 3 in case an increase of telecommunication cables is needed later on.
Several types of PVC pipe such as foam conduit pipe have been utilized to form the conduit pipe 3. The conduit pipe is formed by connecting a plurality of such PVC pipes whose lengths are approximately 6 m. However, since the conduit pipes having a length of 6 m cannot be put into the cable tunnel through an opening of a manhole, the entire numbers of conduit pipes that can be accommodated within the cable tunnel must be installed all together at the same time when the cable tunnel is built. Further, since the conduit pipes occupy a lot of space, it is difficult to carry a great number of pipes at a time. Still further, connection parts of the conduit pipe 3 have larger diameter than any other part thereof, thereby reducing the number of conduit pipes to be installed within the cable tunnel. As a result, the number of communication cables 4 that can be arranged within the conduit pipes 3 is decreased as well.
In the case of using a PE pipe instead of a PVC pipe as a conduit pipe, comparatively larger number of conduit pipes may be installed in a cable tunnel because the PE pipe has no connection part. However, the PE pipe generally has a diameter of 100 mm, and thus it is difficult to carry the PE pipes because the diameter of a bobbin becomes excessively enlarged when the PE pipes are wound.
It is, therefore, the object of the present invention to provide a conduit pipe offering an effective use of an inner space of a cable tunnel. The conduit pipe is made of soft materials and longitudinally divided into a plurality of divided bodies which are kept disconnected at the time of conveyance and then assembled at the time of installation.
In accordance with an aspect of the present invention, there is provided a conduit pipe a plurality of which are installed within a cable tunnel and within which telecommunication cables are built. The conduit pipe comprises a plurality of divided bodies to be connected to form a single conduit pipe, wherein each divided body is equipped at one longitudinal side with retaining parts and at the other longitudinal side with protruded parts.